CN111121136A

CN111121136A - Heating system based on multi-mode heat supply

Info

Publication number: CN111121136A
Application number: CN201911391446.0A
Authority: CN
Inventors: 李筛; 李豪举; 葛仁君; 张景珊; 张亚秋
Original assignee: Solareast Holdings Co Ltd
Current assignee: Solareast Holdings Co Ltd
Priority date: 2019-12-30
Filing date: 2019-12-30
Publication date: 2020-05-08

Abstract

The invention discloses a heating system based on multi-mode heat supply, which comprises a first heat supply device, a first heat exchange device, a second heat exchange device and a heat pump, wherein the first heat exchange device is connected with the first heat exchange device; the first heat supply device and the heat medium channel of the first heat exchange device are connected end to form a first circulation loop, and the refrigerant channel of the first heat exchange device and the heat medium channel of the second heat exchange device are connected end to form a second circulation loop; the inlet of a heat medium channel of the heat pump is connected with a low-temperature pipe of the second circulation loop through a first high-temperature pipe, the inlet of the heat medium channel of the heat pump is connected with the high-temperature pipe of the second circulation loop through a second high-temperature pipe, and the outlet of the heat medium channel of the heat pump is connected with the low-temperature pipe of the second circulation loop through the low-temperature pipe; the first high-temperature pipe and the second high-temperature pipe are alternatively communicated; and the refrigerant channel of the heat pump and the refrigerant channel of the second heat exchange device are connected in series to form a third circulation loop, and the third circulation loop is used for connecting a heat consumer. The invention makes up the heat gap under the working condition of insufficient heat supply through the heat pump, and ensures the heat stability in the user side pipe network.

Description

Heating system based on multi-mode heat supply

Technical Field

The invention belongs to the technical field of heating, and particularly relates to a heating system based on multi-mode heat supply.

Background

Solar energy is the cleanest renewable energy source, and the solar heating is one of important solutions at present with increasingly serious environmental pollution and shortage of fossil energy. At present, a large-scale cross-season heating system in China is more and more emphasized, but solar energy is easily influenced by weather, so that other energy sources are needed for assistance. Air source heat pumps are also included in many countries and regions as renewable energy sources, and a combination of solar energy and air source heat pumps is the most desirable clean heating means. However, there is no case in which both can be organically combined to realize efficient heating.

Disclosure of Invention

The invention aims to overcome the problems in the prior art and provide a heating system based on multi-mode heat supply, which can combine a heat pump and other heat supply equipment to realize the purpose of heat supply under different working conditions.

In order to solve the prior art problem, the invention discloses a heating system based on multi-mode heat supply, which comprises a first heat supply device, a first heat exchange device, a second heat exchange device and a heat pump; the first heat supply device and the heat medium channel of the first heat exchange device are connected end to form a first circulation loop, and the refrigerant channel of the first heat exchange device and the heat medium channel of the second heat exchange device are connected end to form a second circulation loop;

a heat medium channel inlet of the heat pump is connected with the low-temperature pipe of the second circulation loop through a first high-temperature pipe, the heat medium channel inlet of the heat pump is connected with the high-temperature pipe of the second circulation loop through a second high-temperature pipe, and a heat medium channel outlet of the heat pump is connected with the low-temperature pipe of the second circulation loop through a low-temperature pipe; the first high-temperature pipe and the second high-temperature pipe are alternatively communicated;

and the refrigerant channel of the heat pump and the refrigerant channel of the second heat exchange device are connected in series to form a third circulation loop, and the third circulation loop is used for connecting a heat consumer.

Further, when the first high-temperature pipe is conducted, the heat-conducting medium discharged by the second heat exchange device firstly enters the heat pump through the first high-temperature pipe and then returns to the low-temperature pipe of the second circulation loop through the low-temperature pipe;

when the second high-temperature pipe is conducted, the heat-conducting medium in the high-temperature pipe of the second circulation loop firstly enters the heat pump through the second high-temperature pipe and then returns to the low-temperature pipe of the second circulation loop through the low-temperature pipe.

Further, the device also comprises a heat storage device; the heat storage device is connected between the low-temperature pipe and the high-temperature pipe of the second circulation loop.

Furthermore, the heat storage device is also provided with an intermediate-temperature port, the second circulation loop is also provided with an intermediate-temperature pipe, and the intermediate-temperature port of the heat storage device is connected with the high-temperature pipe of the second circulation loop through the intermediate-temperature pipe; and the medium-temperature pipe and the high-temperature pipe of the second circulation loop are alternatively communicated.

Further, when the high-temperature pipe of the second circulation loop is conducted, the heat-conducting medium sequentially passes through the low-temperature pipe of the second circulation loop and the refrigerant channel of the first heat exchange device and then enters the high-temperature pipe of the second circulation loop;

when the medium temperature pipe of the second circulation loop is conducted, the heat-conducting medium sequentially passes through the low temperature pipe of the second circulation loop and the refrigerant channel of the first heat exchange device and then enters the medium temperature pipe of the second circulation loop.

Further, the heat storage device is a hot water storage pool or a heat storage steel tank.

And a high-temperature port of the second heat supply device is connected into a high-temperature pipe of the third circulation loop.

Further, a low-temperature port of the second heat supply device is connected into a high-temperature pipe of the third circulation loop.

Furthermore, the heat-conducting medium in the high-temperature pipe of the third circulation loop passes through the refrigerant channel of the heat pump and then passes through the second heat supply device.

Further, the second heat supply device is a gas heat supply device or a fuel oil heat supply device.

Further, the third circulation loop is further provided with a first bypass pipe and a second bypass pipe, the first bypass pipe is connected in parallel to the pipes at two ends of the refrigerant channel of the second heat exchange device, and the second bypass pipe is connected in parallel to the pipes at two ends of the refrigerant channel of the heat pump.

Further, the heat pump is a water source heat pump, and the first heat supply device is a solar heat collection device.

The invention has the following beneficial effects:

1. according to the invention, the heat gap of the traditional heating equipment under the working condition of insufficient heat supply is made up through the heat pump, and the stability of heat in the user side pipe network is ensured.

2. The heat pump can independently improve the temperature in the user side pipe network, and can also improve the temperature in the user side pipe network together with the heat supply equipment, so that the operation reliability of the system is improved.

3. The heat supply side equipment can be used for independently increasing the temperature in the user side pipe network, can also be used for supplying heat together with the heat pump, and can also store the heat in the heat storage equipment for only needing from time to time when the heat is sufficient.

4. The heat storage equipment can store heat when the heat is sufficient, and supply heat to a user side pipe network when the heat is insufficient, so that the operation efficiency of the system is ensured.

5. The first heat supply device and the heat pump can directly supply heat to heat users through the heat exchange device without storage, can automatically distribute and store redundant heat in the heat storage device, have high heat supply efficiency, and are particularly suitable for low-temperature heat supply devices such as solar energy and the like.

Drawings

FIG. 1 is a schematic view showing a system configuration of a heating system according to the present invention;

FIG. 2 is a schematic view of the heating system of FIG. 1;

fig. 3 is a schematic diagram of the operation of the heating system shown in fig. 1 in a solar high-temperature heat storage mode (arrows indicate the flow direction of the heat-conducting medium in the mode, and bold portions indicate the flow path);

fig. 4 is a schematic diagram of the operation of the heating system shown in fig. 1 in the solar medium-temperature heat storage mode (arrows indicate the flowing direction of the heat-conducting medium in the mode, and bold portions indicate the flowing path);

fig. 5 is a schematic diagram illustrating the operation of the heating system shown in fig. 1 in a solar single heating mode (arrows indicate the flow direction of the heat transfer medium in the mode, and bold portions indicate the flow paths);

fig. 6 is a schematic diagram of the heating system shown in fig. 1 operating in a solar and heat pump dual heating mode (arrows indicate the flow direction of the heat transfer medium in the mode, and bold portions indicate the flow path);

FIG. 7 is a schematic diagram of the heating system of FIG. 1 operating in a dual heat storage and heat pump mode (arrows indicate the flow direction of the heat transfer medium in this mode, and bold portions indicate the flow paths);

fig. 8 is a schematic diagram illustrating the operation of the heating system shown in fig. 1 in an auxiliary heating mode (arrows indicate the flow direction of the heat transfer medium in the auxiliary heating mode, and bold portions indicate the flow paths).

Detailed Description

The invention is further described below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.

As shown in fig. 1, a heating system based on multi-mode heat supply includes a first heat supply device 1, a first heat exchange device 2, a second heat exchange device 3 and a heat pump 5; the first heat supply device 1 and the heat medium channel of the first heat exchange device 2 are connected end to form a first circulation loop 100, and the refrigerant channel of the first heat exchange device 2 and the heat medium channel of the second heat exchange device 3 are connected end to form a second circulation loop 200.

A heat medium channel inlet of the heat pump 5 is connected to the low-temperature pipe 201 of the second circulation circuit 200 through a first high-temperature pipe 208, the high-temperature pipe 203 of the second circulation circuit 200 through a second high-temperature pipe 210, and a heat medium channel outlet thereof is connected to the low-temperature pipe 201 of the second circulation circuit 200 through a low-temperature pipe 209; the first high temperature pipe 208 and the second high temperature pipe 210 are alternatively conducted.

The refrigerant channel of the heat pump 5 and the refrigerant channel of the second heat exchange device 3 are connected in series to form a third circulation loop 300, and the third circulation loop 300 is used for connecting a heat consumer 7.

As shown in fig. 2, specifically, for the first circulation circuit 100, its high temperature pipe 101 is connected between the high temperature outlet of the first heating apparatus 1 and the heat medium passage inlet of the first heat exchange apparatus 2, and its low temperature pipe 102 is connected between the low temperature inlet of the first heating apparatus 1 and the heat medium passage outlet of the first heat exchange apparatus 2. In the first circulation circuit 100, a pump PU1 is attached to the low-temperature pipe 102.

In the second circulation circuit 200, the high temperature pipe 203 is connected between the refrigerant outlet of the first heat exchanger 2 and the heat medium passage inlet of the second heat exchanger 3, and the low temperature pipe 201 is connected between the refrigerant inlet of the first heat exchanger 2 and the heat medium passage outlet of the second heat exchanger 3. In the second circulation circuit 200, a low-temperature pipe 201 is provided with a pump PU2 and a valve V5, and a high-temperature pipe 203 is provided with a pump PU3, a valve V2, a valve V4 and a valve V7.

In the third circulation circuit 300, the low temperature pipe 301 is connected between the inlet of the refrigerant channel of the second heat exchanger 3 and the outlet of the pipe network where the heat consumer 7 is located, the warm pipe 304 is connected between the outlet of the refrigerant channel of the second heat exchanger 3 and the inlet of the refrigerant channel of the heat pump 5, and the high temperature pipe 302 is connected between the outlet of the refrigerant channel of the heat pump 5 and the inlet of the pipe network where the heat consumer 7 is located. In the third circulation circuit 300, a valve V9 is provided in the low temperature pipe 301, a valve V11 is provided in the medium temperature pipe 304, and a valve V13 and a pump PU4 are provided in the high temperature pipe 302.

When the first high temperature pipe 208 is conducted, the heat transfer medium firstly passes through the second heat exchange device 3, then enters the heat pump 5 through the first high temperature pipe 208, and finally returns to the low temperature pipe 201 of the second circulation loop 200 through the low temperature pipe 209. The first high temperature pipe 208 is provided with a valve V6.

When the second high temperature pipe 210 is conducted, the heat transfer medium in the high temperature pipe 203 of the second circulation loop 200 firstly enters the heat pump 5 through the second high temperature pipe 210, and then returns to the low temperature pipe 201 of the second circulation loop 200 through the low temperature pipe 209. The second high temperature pipe 210 is provided with a valve V8. Note that the connection point of the first high temperature pipe 208 to the low temperature pipe 201 of the second circuit 200 is located before the valve of the valve V5, and the connection point of the low temperature pipe 209 to the low temperature pipe 201 of the second circuit 200 is located after the valve of the valve V5. The valves V8 and V6 control the conductance of the first high temperature pipe 208 and the second high temperature pipe 210.

As shown in fig. 2, in a preferred embodiment, the heating system further includes a heat storage device 4; the thermal storage device 4 is interposed between the low-temperature pipe 201 and the high-temperature pipe of the second circulation circuit 200. Specifically, the thermal storage device 4 has a low temperature port and a high temperature port, and the low temperature port extends to a height lower than the high temperature port in the thermal storage device 4, so that the low temperature water in the lower layer can be heated by heat exchange and then returned to the upper layer. The low-temperature port of the thermal storage device 4 is connected to the low-temperature pipe 201 of the second circulation circuit 200 through the low-temperature pipe 204, and the high-temperature port thereof is connected to the high-temperature pipe 203 of the second circulation circuit 200 through the high-temperature pipe 206. In this way, the low-temperature water in the thermal storage device 4 can be heated by the first heat exchange device 2 and then returned to the thermal storage device 4.

In a preferred embodiment, the first heat supply device 1 inevitably has a reduced heat generation efficiency due to weather or other factors, and therefore cannot heat the low-temperature water in the thermal storage device 4 to a high temperature, and therefore, in order to achieve the purpose, the low-temperature water may be heated to a medium temperature and then may be returned to the middle layer of the thermal storage device 4.

The thermal storage device 4 also has an intermediate-temperature port that participates in the second circulation loop. The extension height of the medium temperature port in the thermal storage device 4 is located between the extension heights of the low temperature port and the high temperature port, and the medium temperature port is used for circulation of medium temperature water in the middle layer. Specifically, the medium-temperature port of the thermal storage device 4 is connected to different positions of the high-temperature pipe of the second circulation circuit 200 through a first medium-temperature branch pipe 202 and a second medium-temperature branch pipe 207, respectively, wherein the first medium-temperature branch pipe 202 is connected before the valve of the valve V2, and the second medium-temperature branch pipe 207 is connected after the valve of the valve V4 and before the pump of the pump PU 3.

In a preferred embodiment, in order to avoid that other equipment of the system stops and cannot generate heat, the heating system further comprises a second heating device 6, and a high-temperature port of the second heating device 6 is connected into a high-temperature pipe 302 of the third circulation loop 300. If the second heating device 6 is also involved in the medium circulation of the system, its low temperature port is also connected to the high temperature pipe 302 of the third circulation circuit, and a valve V13 is provided between the connection points of the high temperature pipe 302 and the low temperature port.

When the first heat supply device 1 or the second heat supply device 6 supplies heat alone, the heat-conducting medium in the third circulation loop 300 does not pass through other equipment which does not work as much as possible, so that the heat-conducting path is shortened, and the pipe loss is reduced. Therefore, in third circulation circuit 300, first bypass pipe 305 is connected between low temperature pipe 301 and medium temperature pipe 304, valve V10 is provided in first bypass pipe 305, second bypass pipe 303 is connected between medium temperature pipe 304 and high temperature pipe 302, and valve V12 is provided in second bypass pipe 303.

Note that one end of the first bypass pipe 305 is positioned before the valve V9, and the other end is positioned before the valve V11. One end of the second bypass pipe 303 is located before the valve of the valve V11, and the other end is located before the valves of the valve V14 and the valve V13. It can be seen that first bypass pipe 305 functions to bypass second heat exchange means 3 and second bypass pipe 303 functions to bypass heat pump 5.

In a preferred embodiment, the thermal storage device 4 is a thermal storage water tank or a thermal storage steel tank.

In a preferred embodiment, the second heating means 6 is a gas heating means or an oil heating means.

In a preferred embodiment, the number of heat pumps 5 is two, and when one of the heat pumps 5 fails, the other heat pump 5 can still operate in the same operation mode, maintaining the stability of the whole system. The heat pump 5 is a water source heat pump, and the first heat supply device 1 is a solar heat collection device.

It should be noted that, for the pipeline, when the inlet and outlet of the equipment need to communicate two or more pipelines at the same time, a multi-way joint is usually needed to realize specific connection, so as to meet the requirement that the media passing through the inlet and outlet of the equipment can be shunted by the multi-way joint or the media of a plurality of pipelines can be converged by the multi-way joint.

The heating apparatus of the present invention has various operation modes, and the principle and process thereof are explained below with reference to fig. 3 to 8, respectively.

Firstly, a solar high-temperature heat storage mode: as shown in fig. 3, when the first heating apparatus 1 is in a high power state, for example, in a weather with strong solar radiation, the solar energy apparatus generates heat with high efficiency, but the heat of the heat user 7 is under a working condition without heat demand. In this mode, pump PU1 and pump PU2 are operating, valve V2 is open, and the other pumps and valves are closed.

Starting from the first heat supply device 1, the flow path of the heat transfer medium in the first circulation loop 100 in this mode is: first heat supply unit 1 → high temperature pipe 101 → heat medium passage of first heat exchange unit 2 → low temperature pipe 102 → first heat supply unit 1. Thereby realizing the heat transfer from the first heat supply device 1 to the first heat exchange device 2. The high temperature pipe of the second circulation circuit 200 is in a conduction state.

Similarly, starting from the first heat exchange device 2, the flow path of the heat transfer medium in the second circulation loop 200 in this mode is: the refrigerant passage of the first heat exchange device 2 → the high-temperature tube 203 → the heat storage device 4 → the low-temperature tube 201 → the refrigerant passage of the first heat exchange device 2. Whereby the transfer of heat from the first heat exchange means 2 to the thermal storage means 4 is effected. For the heat storage device 4, low-temperature water in the lower layer inside the heat storage device is heated and then flows back to the upper layer, so that high-temperature heat storage is realized.

Secondly, a solar medium-temperature heat storage mode: as shown in fig. 4, when the heat generating efficiency of the first heat supplying means 1 is decreased, for example, when the solar radiation is decreased, the first heat supplying means 1 cannot heat the low temperature water to the high temperature water. In this mode, pump PU1 and pump PU2 are operating, valve V1 is open, and the other pumps and valves are closed.

The flow path of the first circulation circuit 100 is the same as that in the high temperature heat accumulation mode, and thus, the description thereof is omitted. Starting from the first heat exchange device 2, the flow path of the heat transfer medium in the second circulation loop 200 in this mode is: the refrigerant passage of the first heat exchange device 2 → the first intermediate-temperature branch pipe 203 → the thermal storage device 4 → the low-temperature pipe 201 → the refrigerant passage of the first heat exchange device 2. Whereby the transfer of heat from the first heat exchange means 2 to the thermal storage means 4 is effected. For the heat storage device 4, the low-temperature water in the lower layer inside the heat storage device is heated and then flows back to the middle layer, so that medium-temperature heat storage is realized. The medium temperature tube of the second circulation loop 200 is in a conductive state.

Thirdly, a solar energy independent heating mode: as shown in fig. 5, when the first heating apparatus 1 generates heat with high efficiency, the heat demand of the heat consumer side can be satisfied. The first heating device 1 is directly used as a heat source to heat the heat consumer 7. In this mode, pump PU1, pump PU2, pump PU3, and pump PU4 are all operating, valve V2, valve V4, valve V5, valve V7, valve V9, valve V12, and valve V13 are open, and the other pumps and valves are closed.

The flow path of the first circulation circuit 100 is the same as that in the high temperature heat accumulation mode, and thus, the description thereof is omitted. Starting from the first heat exchange device 2, the flow path of the heat transfer medium in the second circulation loop 200 in this mode is: the refrigerant passage of the first heat exchanger 2 → the high temperature pipe 203 → the heat medium passage of the second heat exchanger 3 → the low temperature pipe 201 → the refrigerant passage of the first heat exchanger 2. Thereby effecting a transfer of heat from the first heat exchange means 2 to the second heat exchange means 3.

Similarly, starting from the second heat exchange device 3, the flow path of the heat transfer medium in the third circulation loop 300 in this mode is: the refrigerant passage of the second heat exchange device 3 → the second bypass pipe 303 → the high temperature pipe 302 → the hot user 7 → the low temperature pipe 301 → the refrigerant passage of the second heat exchange device 3. Thereby effecting a transfer of heat from the second heat exchange means 3 to the heat consumer 7.

It should be noted that when the heat provided by the first heat supplying device 1 exceeds the demand of the heat consumer 7, the excess heat can be stored by the heat storage device 4, and the flow path of the heat conducting medium has been described in the first mode, and therefore, the description thereof is omitted.

Fourthly, a solar energy and heat pump dual heating mode: when the heat production of the first heating apparatus 1 decreases and is insufficient to meet the heat demand of the heat consumer 7, as shown in fig. 6, the heat transfer medium in the third circulation circuit 300 is heated to a desired temperature by the heat pump 5. In this mode, pump PU1, pump PU2, pump PU3, and pump P4 are operating with valve V1, valve V3, valve V6, valve V7, valve V8, valve V9, valve V11, and valve V13 open, and the other pumps and valves are closed. The first high temperature tube 208 is in a conducting state.

The flow path of the first circulation circuit 100 is the same as that in the high temperature heat accumulation mode, and thus, the description thereof is omitted. Starting from the first heat exchange device 2, the flow path of the heat transfer medium in the second circulation loop 200 is: the refrigerant passage of the first heat exchanger 2 → the first intermediate-temperature branch pipe 202 → the second intermediate-temperature branch pipe 207 → the heat medium passage of the second heat exchanger 3 → the low-temperature pipe 201 → the first high-temperature pipe 208 → the heat medium passage of the heat pump 5 → the high-temperature pipe 209 → the low-temperature pipe 201 → the refrigerant passage of the first heat exchanger 2. Thereby realizing that the heat flows from the first heat exchange device 2 to the second heat exchange device 3 and then to the heat pump 5.

Similarly, starting from the second heat exchange device 3, the flow path of the heat transfer medium in the third circulation loop 300 in this mode is: the refrigerant passage of the second heat exchange device 3 → the low-temperature pipe 304 → the refrigerant passage of the heat pump 5 → the high-temperature pipe 302 → the hot user 7 → the low-temperature pipe 301 → the refrigerant passage of the second heat exchange device 3.

It should be noted that, when the heat generated by the first heat supply device 1 is reduced due to poor solar radiation, and the first heat supply device 1 cannot provide enough heat, the heat stored in the heat storage device 4 may participate in heat supply, and the flow path of the heat-conducting medium is not described in detail.

In this mode, since the temperature required by the heat consumer 7 is high, which causes an excessive temperature rise, the heat pump 5 cannot heat the low-temperature heat-conducting medium to the temperature required by the heat consumer 7 with high efficiency, and therefore it is very important to fully utilize the heat in the second circulation circuit 200. Therefore, the heat-conducting medium in the low-temperature pipe 301 is heated to the intermediate temperature by the second heat exchanging device 3 before entering the heat pump 5, so that the heating temperature difference of the heat pump 5 is reduced, and the heat pump 5 can heat the heat-conducting medium in the medium-temperature pipe 304 to the temperature required by the heat consumer 7 with high efficiency. The heat-conducting medium coming out of the second heat exchange device 3 enters the heat pump 5, the residual heat of the heat-conducting medium in the low-temperature pipe 201 is utilized to heat the heat-conducting medium in the refrigerant pipeline through the action of the heat pump 5, and finally the heat-conducting medium returns to the low-temperature pipe 201 to be heated again.

Fifthly, a heat storage and heat pump double heat supply mode: as shown in fig. 7, when the first heat supply device 1 cannot operate normally due to poor solar radiation, and the heat storage device 4 cannot meet the temperature requirement of the hot user for supplying water, and the temperature in the heat storage device 4 is not much different from the temperature in the low-temperature pipe 304 of the third circulation loop 300, the heat exchange significance of the second heat exchange device 3 is not great, so that the heat storage device 4 directly operates with the heat pump 5 to participate in heat supply. In this mode, pump PU3 and pump P4 are operating, with valve V3, valve V8, valve V10, valve V11, and valve V13 open, and the other pumps and valves closed. The second high temperature pipe 210 is in a conductive state.

Starting from the thermal storage device 4, the flow path of the heat transfer medium in the second circulation circuit 200 in this mode is: the heat storage device 4 → the second intermediate-temperature branch pipe 207 → the high-temperature pipe 203 → the second high-temperature pipe 210 → the heat medium passage of the heat pump 5 → the low-temperature pipe 209 → the low-temperature pipe 201 → the heat storage device 4. Whereby a transfer of heat from the thermal storage device 4 to the heat pump 5 is achieved.

Starting from the heat pump 5, the flow path of the heat transfer medium in the third circulation circuit 300 in this mode is: the refrigerant passage of the heat pump 5 → the high temperature pipe 302 → the heat consumer 7 → the low temperature pipe 301 → the refrigerant passage of the second heat exchange device 3 → the low temperature pipe 304 → the refrigerant passage of the heat pump 5. Thereby enabling the transfer of heat from the heat pump 5 to the heat consumer 7.

Note that, if the temperature of the water in the thermal storage device 4 exceeds the temperature in the low temperature pipe 304 in the third circulation circuit 300, the difference is large. In this case, since the temperature required by the heat consumer 7 is high, which causes an excessive temperature rise, the heat pump 5 cannot heat the low-temperature heat-conducting medium to the temperature required by the heat consumer 7 with high efficiency, and therefore it is very important to fully utilize the heat in the second circulation circuit 200. Therefore, the heat-conducting medium in the low-temperature pipe 301 is heated to the intermediate temperature by the second heat exchanging device 3 before entering the heat pump 5, so that the heating temperature difference of the heat pump 5 is reduced, and the heat pump 5 can heat the heat-conducting medium in the medium-temperature pipe 304 to the temperature required by the heat consumer 7 with high efficiency. The heat-conducting medium coming out of the second heat exchange device 3 enters the heat pump 5, the residual heat of the heat-conducting medium in the low-temperature pipe 201 is utilized to heat the heat-conducting medium in the refrigerant pipeline through the action of the heat pump 5, and finally the heat-conducting medium returns to the low-temperature pipe 201 to be heated again. In this process, the flowing direction of the heat transfer medium in the second circulation loop 200 and the third circulation loop 300 in the fourth mode is the same, and thus the description thereof is omitted.

Sixthly, an auxiliary heating mode: as an alternative example of the dual heating mode of solar energy and heat pump, as shown in fig. 8, when the heat pump 5 cannot work normally, the second heating apparatus 6 replaces the heat pump 5 to supply heat with the first heating apparatus 1. In this mode, pump PU1, pump PU2, pump PU3, and pump PU4 are operating with valve V1, valve V3, valve V5, valve V7, valve V9, valve V12, and valve 14 open, and the other pumps and valves are closed.

The flow path of the first circulation circuit 100 is the same as that in the high temperature heat accumulation mode, and the flow path of the second circulation circuit 200 is the same as that in the solar and heat pump dual heating mode, and thus, detailed description thereof is omitted.

Starting from the second heat exchanging device 3, the flow path of the heat transfer medium in the third circulation loop 300 in this mode is: the refrigerant passage of the second heat exchange device 3 → the second bypass pipe 303 → the second heat supply device 6 → the high temperature pipe 302 → the heat consumer 7 → the low temperature pipe 301 → the refrigerant passage of the second heat exchange device 3. Thereby, the second heat exchange device 3 is used for heating to a certain temperature, and then the second heat supply device 6 is used for heating to the temperature required by the heat user 7.

It should be noted that the above modes are only preferred operating modes with low energy consumption, high thermal efficiency, and the like, and the operating modes of the heating system of the present invention are not limited to the above modes, and on the premise of the provided devices and connection modes, other modes for combined heat supply may be provided, and therefore, details are not described again.

In the present invention, the "refrigerant channel" refers to a channel through which a temperature increasing process is completed with a low inlet temperature and a high outlet temperature, and correspondingly, the "heat medium channel" refers to a channel through which a temperature decreasing process is completed with a high inlet temperature and a low outlet temperature.

The above is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.

Claims

1. A heating system based on multi-mode heat supply, its characterized in that: comprises a first heat supply device (1), a first heat exchange device (2), a second heat exchange device (3) and a heat pump (5); the first heat supply device (1) and the heat medium channel of the first heat exchange device (2) are connected end to form a first circulation loop (100), and the refrigerant channel of the first heat exchange device (2) and the heat medium channel of the second heat exchange device (3) are connected end to form a second circulation loop (200);

a heat medium channel inlet of the heat pump (5) is connected with a low-temperature pipe (201) of the second circulation loop (200) through a first high-temperature pipe (208), a high-temperature pipe (203) of the second circulation loop (200) is connected through a second high-temperature pipe (210), and a heat medium channel outlet is connected with the low-temperature pipe (201) of the second circulation loop (200) through a low-temperature pipe (209); the first high-temperature pipe (208) and the second high-temperature pipe (210) are alternatively conducted;

and a refrigerant channel of the heat pump (5) and a refrigerant channel of the second heat exchange device (3) are connected in series to form a third circulation loop (300), and the third circulation loop (300) is used for being connected with a heat consumer (7).

2. A heating system based on multi-mode heat supply according to claim 1, characterized in that: when the first high-temperature pipe (208) is conducted, the heat-conducting medium discharged by the second heat exchange device (3) firstly enters the heat pump (5) through the first high-temperature pipe (208), and then returns to the low-temperature pipe (201) of the second circulation loop (200) through the low-temperature pipe (209);

when the second high-temperature pipe (210) is conducted, the heat-conducting medium in the high-temperature pipe (203) of the second circulation loop (200) firstly enters the heat pump (5) through the second high-temperature pipe (210) and then returns to the low-temperature pipe (201) of the second circulation loop (200) through the low-temperature pipe (209).

3. A heating system based on multi-mode heat supply according to claim 2, characterized in that: also comprises a heat storage device (4); the heat storage device (4) is connected between a low-temperature pipe (201) and a high-temperature pipe of the second circulation loop (200).

4. A heating system based on multi-mode heat supply according to claim 3, characterized in that: the heat storage device (4) is also provided with an intermediate-temperature port, the second circulation loop (200) is also provided with an intermediate-temperature pipe (202), and the intermediate-temperature port of the heat storage device (4) is connected with the high-temperature pipe (203) of the second circulation loop (200) through the intermediate-temperature pipe (202); the medium temperature pipe (202) and the high temperature pipe (203) of the second circulation loop (200) are alternatively communicated.

5. A heating system based on multi-mode heat supply according to claim 4, characterized in that: when the high-temperature pipe (203) of the second circulation loop (200) is conducted, the heat-conducting medium sequentially passes through the low-temperature pipe (201) of the second circulation loop (200) and the refrigerant channel of the first heat exchange device (2) and then enters the high-temperature pipe (203) of the second circulation loop (200);

when the medium-temperature pipe (202) of the second circulation loop (200) is communicated, the heat-conducting medium sequentially passes through the low-temperature pipe (201) of the second circulation loop (200) and the refrigerant channel of the first heat exchange device (2) and then enters the medium-temperature pipe (202) of the second circulation loop (200).

6. A heating system based on multi-mode heat supply according to claim 3, characterized in that: the heat storage device (4) is a hot water storage pool or a heat storage steel tank.

7. A heating system based on multi-mode heat supply according to claim 1, characterized in that: the system also comprises a second heat supply device (6), and a high-temperature port of the second heat supply device (6) is connected into a high-temperature pipe (302) of the third circulation loop (300).

8. A heating system based on multi-mode heat supply according to claim 7, characterized in that: the low-temperature port of the second heat supply device (6) is connected into the high-temperature pipe (302) of the third circulation loop (300).

9. A heating system based on multi-mode heat supply according to claim 8, wherein: and the heat-conducting medium in the high-temperature pipe (302) of the third circulation loop (300) firstly passes through a refrigerant channel of the heat pump (5) and then passes through the second heat supply device (6).

10. A heating system based on multi-mode heat supply according to claim 7, characterized in that: the second heat supply device (6) is a gas heat supply device or a fuel oil heat supply device.

11. A heating system based on multi-mode heat supply according to claim 1, characterized in that: the third circulation loop (300) is further provided with a first bypass pipe (305) and a second bypass pipe (304), the first bypass pipe (305) is connected in parallel to pipes at two ends of a refrigerant channel of the second heat exchange device (3), and the second bypass pipe (304) is connected in parallel to pipes at two ends of the refrigerant channel of the heat pump (5).

12. A heating system based on multi-mode heat supply according to claim 1, characterized in that: the heat pump (5) is a water source heat pump, and the first heat supply device (1) is a solar heat collection device.